Control for power hammers



Dec. 9, 1941. G. R. MURRAY CONTROL FOR POWER HAMMERS Filed June 17, 1940 -2 Sheet-Shet 2 Patented Dec. 9, 1 941 UNITED STATES V 1 2,265,922? coNTR oL we PoWI'ianT'lw 'f "E'R s George R. to Chamber'sburg l'lngineermg' Gompany Ghambersburg, 'Pa., a 'eorporatidno'f Pennsylvania Application time 17, 1940; sriafNoianMe 7 claims. (Cl.; 1 2l30) mvention relates to a control for, flui.d pressure-operated hammers and, more particularly, to a control of that type wherein the movement of the ram is controlled by coactin g cam surfaces on the ram and a linkage mecha nism connected with the valve supplyingand exhausting fluid pressure from the power cylina Such devices as heretofore constructed 90inpri se Ialinkage carried cam which coacts with an inclined surface formed on the ram. This inclined surface, insoiaras its engagement with the cam or the linkage is concerned, has been made substantially continuous; that is to say, there is permanent engagement duringany normal operation of the hammer 'I'hrough adjustment of the linkage, the operator can set the hammer to remain at any given level above the fanvil, but with such prior jconstructicns there is continuous oscillationof the ram Icy reason of the fact that the cam engagement permits suflj cient oscillation ofthe valve .coniirolling supply and exhaust to 'intermittently introduce pressure to opposite ends of the cylinder. operation obviously, results not only considerable wear on'the working parts, but likewise results in a waste of fluid pressure. c An important object of the present invention t i d mn o a n t c i n. suc that the m m e b u t x resta n selec ed point simply by. release of the ordinary operating treadle with which the linkage mechanism is supplied, or be made to'oscillate asdesired. A Another objector the inventionis -to accorne plish this end with but slight modification of the present hammer structure andat a cost. no greater than is met with the production of 'the present control mechanism. r V I These and other objects I attain bythe co ne struction shown in the accompanying drawings he m r 7 on n Fig. 1 is a diagrammatic 'view illustrating the hammer provided with a con-trol constructed in accordance with my invention; c v

Fig. 2 isa plan view of the rarnand the associated portions of the control mechanism; V

Fig. 3 is asection on line A -A ofFlg 2 the ram being shown in the position of rest; and

. Fig. 4 is a View similar to that of Fig. 3, but

showing the ram in the position where oscillation 5 will take place. 7

Referring now more particularly to the drawings, the numeral ill generally designates the a of a ower amm r; ll, heanvil wi h which it coacts; l2, apower cylinder the piston I3 of 5 isticon'rrectdf to lithe rain l 0 through rod Al 5,:a v'aiye for controlling the movement 'gif theg-plstoni'and rain. the illustration of ,Ffig. 'l the mantle ,valye element [5 is shown as disposed inwanfihtermediate. position where no fiiiid'prssure'from inlet 11 may reach either of theconduits It} or l9 leading respectively to the u per, :and lower ehclsioi' ,cylinder 12. Upon downward mo'vment of this valve, fluid pressure n exhaust from the upper end of vcylinderjl 'z upper d oi the cy1in 'derf;aiid exhaust will take place belowthe valve element to eart en-l,

The position of the valve is controlledthrough a linkage mechanism 24 including av lever '25 ing a c am surface 29 on I'il. "Iheother arm of this ihelllcrahlgleyer is linked to valve elements to operate the same, connections being 1. qi-p a 2 y v a ve mit fluid pressure to the w de e n -10 that l Ifthe treaolle isonly parwally. re a e (th r m. tw l. Q Q t e l u wardl aa thepos illat at t epoint det rmi d J93 the, tread q os t on.- A a ve po ted wtwth slp lla n wi l on nue even after the ee le ha abeienh qm lete y re ea ed 7 v a cg d a ewith my. n e tion, t cam s riace Z9 is hrokenv up i into -;tWQ sect-ions, the, first of which, indicated at 30, is inclined-With respect 5 to the-axisof -the ramand is arranged uppermost,

determined through adjustment of the linkage at 21. Upon depression of pedal 26, the cam will come into operative engagement with the section 30 of cam 29, with the immediate result that operation of the hammer will begin. At this time, the hammer will operate after the manner of the usual hammer above described, the hame hammers, a ram, a cylinder to operate the mm, a valve controlling the intake and exhaust of the cylinder and having a neutral position, a cam linked to the valve to operate the same, a coacting cam surface on the ram, said cam surface embodying two sections engageable by the cam one of which is so constructed and arranged that when it is engaged with the cam movement of the ram will cause shifting of said valve and the other of which is so constructed that during its engagement with the cam the valve will remain s tationary and in its neutral position, means to bodily shift said cam longitudinally of the cam surface of the ram comprising a lever pivoted to swingin a plane substantially radial to the ram axis and upporting said cam, and a two-position operating member connected to the lever to shift mer following the treadle and oscillating at any V point where the treadle may be held if the treadle be only partially released. However, upon complete release of the treadle, the hammer will elevate until the cam surface 3| is coacting with cam 28, at which time the ram will become stationary. The position of the ramat this time may,- of course, be regulated through adjustment It will be obvious that by an arrangement of this character a considerable saving in fiuidpressure may be effected, and it will also be obvious that there will be a correspondingly reduced wear and tear upon the elements of the control which are'under constant motionas long as the cam 28 is engaged with the working section 30 of cam 29. It will also be obvious that the construction illustrated is capable of considerable modification without departing from the spirit of my invention and I, accordingly, do not wish to be understood as limiting myself thereto except as hereinafter claimed.

I claim:

1.-In a control for fluid-pressure-operated hammers, a ram, a cylinder to operate the ram, a valve controlling the intake and exhaust of the cylinder and having a neutral position, a cam linked to the valve to operate thesame, a coacting cam-surface onthe ram, said cam surface embodying two sections engageable bythe cam one of which is so constructed and arranged that when it is engaged with-the cam movement of the ram will cause shifting of said valve and the other of which is so constructed that during its engagement-with the cam the valve will remain stationary and inits neutral position, and means to bodily shiftsaid cam longitudinally of the cam surface of the ram.

2. In a control for fluid-pressure-operated hammers, a ram, a cylinder to operate the ram, a valve controlling the intake and exhaust of the cylinder and having a neutral position, a cam linked to the valve to operate the same, a coacting cam surface on the ram, said cam surface embodying two sections engageable by the cam one of which is so constructed and arranged that when it is engaged with the cam movement of the ram will cause shifting of said valve and the other of which is so constructed that during its engagement with the cam the valve will remain stationary and in its neutral position, means to bodily shift said cam longitudinally of the cam surface of the ram comprising-a lever pivoted to swing in a-plane substantiallyradial to the ram axis and supporting said cam, and a two-position operatingmember connected to the lever t shift the same. I Y

3. In a control for fluid-pressure-operated the same, the connections between the lever and operating member comprising an adjustable link.

,4..In a control for fluid-pressure-operated hammers, a ram, a cylinder to operate the ram, a valve controlling the intake and exhaust of the cylinder and having a neutral position, a cam linked to the valve to operate the same, a coacting cam surface on the ram,-said cam surface embodying two sections engageable by the cam one of which is inclined with relation to the ram axis whereby when it i engaged with the cam movement of the ram will cause shifting of said valve and the other of which is parallel to the ram axis whereby during its engagement with the cam the valve will remain stationary and in its neutral position, and means to bodily shift said cam longitudinally of the cam surface of the ram to selectively engage the cam with either section of the cam surface of the ram.

5.In a control for iiuid-pressure-operated hammers, a ram, a cylinder to operate the ram, a valve controlling the intake and exhaust of the cylinder and having a neutral position, a cam linked to the valve to operate the same, a coacting cam surface on the ram, said cam surface embodying two sections engageable by the cam one of-which is inclined with relation to the ram axis whereby when it is engaged with the cam movement of the ram will cause shifting of said valve and the other of which is parallel to the ram axis whereby during its engagement with the cam the valve will remain stationary and in its neutral position, and means to bodily shift said cam longitudinally of the cam surface of the ram to selectively engage the cam with either section of the cam surface of the ram comprising a lever pivoted to swing in a plane substantially radial to the ram axis and supporting said cam,

and a two-position operating member connected to the lever to shift the same.

6. In a control for fiuid-pressure-operated hammers, a ram, a cylinder to operate the ram, a valve controlling the intake and exhaust of the cylinder and having a neutral position, a cam linked to the valve to operate the same, a coacting cam surface on the ram, said cam surface embodying two sections engageable by the cam one of which is inclined with relation to the ram axis whereby when it is engaged with the cam movement of the ram will cause shifting of said valve and the other of which is parallel to the ram axis whereby during its engagement with the cam the valve will remain stationary and in its neutral position, and means 'to bodily shift said cam longitudinally of the cam surface of the ram to selectively engage the cam with either section of the cam surface of the ram comprising a lever pivoted to swing in a cam one of which is inclined with relation to the ram axis whereby when it is engaged with the cam movement of the ram will cause shifting of said valve and the other of which is parallel to the ram axis whereby during its engagement with the earn the valve will remain stationary and in its neutral position, and means to bodily shift said cam to selectively engage the cam with either section of the cam surface of the 10 ram.

GEORGE R. MURRAY. 

